Try swapping out Calderon?
Here is one idea. Why not let Hedo play full time starting point forward, and have Jack or Wright start in place of Calderon? The objective is to lock down opposing point guards. Have Calderon come off the bench and tear up backup point guards.
There is more than enough firepower on the floor with Hedo, Bosh and Bargs starting. Improving the defense at the one spot should hopefully be a substantial difference maker...means that Bosh and Bargs can get even more boards. Hedo I think is a lot more creative than Calderon, and will do a better job of running the offense (in particular, making sure that Bargs is fed.)
And this has the nice effect of making making Hedo and Bargs less disinterested.
The major downside is that it decreases Calderon's trade value (personally, I'd prefer trading him, but it is unclear if that is feasible..)